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大气与地形环境对林火蔓延的影响研究--以山西一次森林火灾为例 被引量:2
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作者 王宇虹 赵鲁强 +4 位作者 杨晓丹 梁莉 袁晓玉 任俐文 张辉 《灾害学》 CSCD 北大核心 2023年第3期118-125,共8页
为了深入认识林火蔓延特征及大气、地形等对林火行为的影响,选取2020年“3·17”山西晋中森林火灾,利用高分辨率地理信息、卫星遥感林火监测数据和气象观测对此次林火行为进行分析研究,同时运用林火—大气耦合WRF-Fire模式进行数值... 为了深入认识林火蔓延特征及大气、地形等对林火行为的影响,选取2020年“3·17”山西晋中森林火灾,利用高分辨率地理信息、卫星遥感林火监测数据和气象观测对此次林火行为进行分析研究,同时运用林火—大气耦合WRF-Fire模式进行数值模拟。研究发现:①在可燃物载量相对稳定情况下,林火蔓延与地形和大气环境(大尺度天气系统和小尺度局地小气候)密切相关,尤其是风的变化;②数值模拟过火区范围和形状、火线蔓延方向和速度以及风向风速变化与实况较为一致,表明WRF-Fire模式可以较准确再现真实火场蔓延情况。分析蔓延速率、蔓延方向、火焰高度、释放热量和水汽等蔓延特征变量和过火区分布情况,该次模拟时效内的林火发展可分为5个阶段,不同阶段蔓延特征显著不同。 展开更多
关键词 林火-大气耦合模式 林火蔓延 森林火灾 数值模拟
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青风藤安全性研究进展 被引量:20
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作者 郑湘锦 任利文 +2 位作者 李婉 王金华 杜冠华 《医药导报》 CAS 北大核心 2019年第11期1430-1433,共4页
青风藤是防己科植物青藤及毛青藤的干燥藤茎,具有降压、抗心律失常、抗炎和抗肿瘤等作用。该文通过查阅文献并结合现代药理研究,分析青风藤的毒性以及引起毒性反应的物质基础和分子机制,评价青风藤毒性反应与药效活性的关系,分析毒性反... 青风藤是防己科植物青藤及毛青藤的干燥藤茎,具有降压、抗心律失常、抗炎和抗肿瘤等作用。该文通过查阅文献并结合现代药理研究,分析青风藤的毒性以及引起毒性反应的物质基础和分子机制,评价青风藤毒性反应与药效活性的关系,分析毒性反应的主要临床表现及对策,以期为科学认识和临床合理应用青风藤提供参考。 展开更多
关键词 青风藤 青藤碱 毒性反应 药效活性
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雷公藤毒性的历史认识与评价 被引量:15
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作者 任利文 郑湘锦 +2 位作者 李婉 王金华 杜冠华 《医药导报》 CAS 北大核心 2021年第5期637-641,共5页
雷公藤是临床常用治疗自身免疫性疾病的一味中药,其毒副反应严重,甚至引发患者死亡。该文通过总结历代典籍对雷公藤毒性的记载,结合现代研究,从毒性反应的临床表现、物质基础、分子机制及减毒策略等方面,评价雷公藤毒性反应与药效活性... 雷公藤是临床常用治疗自身免疫性疾病的一味中药,其毒副反应严重,甚至引发患者死亡。该文通过总结历代典籍对雷公藤毒性的记载,结合现代研究,从毒性反应的临床表现、物质基础、分子机制及减毒策略等方面,评价雷公藤毒性反应与药效活性的关系,以期为雷公藤的科学认识及合理使用提供参考。 展开更多
关键词 雷公藤 药理活性 毒性 分子机制 减毒策略
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无患子媛华不同物候期养分需求特征研究 被引量:2
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作者 刘俊涛 陈义勇 +7 位作者 王立宪 任立文 曹秋丽 王冕之 郑玉琳 翁学煌 赵鹏丽 贾黎明 《热带作物学报》 CSCD 北大核心 2024年第3期533-541,共9页
为了解无患子媛华无性系原料林叶片矿质元素在不同关键物候期动态变化规律,揭示该无性系养分需求特征,为科学制定营养管理制度提供理论依据。以福建省建宁县树龄5、6、7 a的无患子媛华无性系原料林为研究对象,测定展叶期、花序抽生末期... 为了解无患子媛华无性系原料林叶片矿质元素在不同关键物候期动态变化规律,揭示该无性系养分需求特征,为科学制定营养管理制度提供理论依据。以福建省建宁县树龄5、6、7 a的无患子媛华无性系原料林为研究对象,测定展叶期、花序抽生末期、花期末、果实膨大初期、果实转色期、果实成熟期N、P、K、Ca、S、Mg、Fe、Zn、B等含量指标。无患子媛华无性系原料林不同关键物候期叶片中N、P、K、Ca、Mg含量总体呈先降低、再上升、后降低趋势,均在果实膨大初期达到最高;N和P的含量在花序抽生末期和果实膨大初期之间存在显著差异,其K含量在果实膨大初期显著高于其他关键生育期,且在其余生育期之间无显著差异,而Ca含量和Mg含量在展叶期和果实膨大初期存在显著差异(P<0.05),Fe、B含量呈先上升后降低趋势,Fe含量在果实转色期显著高于其余生育期,B含量在花期末急剧降低,且显著低于其余生育期(P<0.05),Zn含量和S含量全年总体无明显变化。3个树龄叶片中N含量和K、P、Mg含量分别呈显著正相关,Ca含量和K、Fe含量分别呈显著正相关,S含量和Zn含量呈显著负相关,Zn含量和S、B含量分别呈显著负相关。坐果期(6—7月底)可作为叶片营养诊断的适宜时期;施肥应考虑各元素间的关联;在花序抽生末期时,此时应及早追施N、P和B肥;在坐果期要适量追肥,同时结合追施微肥。 展开更多
关键词 无患子 无性系 叶片矿质元素 物候期 动态变化
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International Meridian Circle Program 被引量:2
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作者 LIU William WANG Chi +18 位作者 SHEN Xuhui WU Jian BLANC Michel YAN Yihua FU Suiyan YUE Xinan LEI Jiuhou GONG Wei ZHANG Shaodong ZHANG Qinghe WANG Xin YANG Jing ZHANG Xiaoxin GAO Jing XU Jiyao YANG Guotao LI Hui ren liwen YANG Fang 《空间科学学报》 CAS CSCD 北大核心 2020年第5期723-725,共3页
The Earth is buffered from the ferocious onslaught of the solar wind by a thin layer of matter known as the atmosphere and geospace.This layer absorbs energy from irradiance and outburst from the Sun,as well as from d... The Earth is buffered from the ferocious onslaught of the solar wind by a thin layer of matter known as the atmosphere and geospace.This layer absorbs energy from irradiance and outburst from the Sun,as well as from disasters,transient phenomena and anthropogenic emissions originated from Earth.Through complicated physics,the absorbed energy changes the atmospheric and geospace state and sometimes gets re-released to power extreme events such as space weather.Taking place globally,these complicated processes cannot be understood unless they are studied globally.The Chinese scientists have proposed the International Meridian Circle Program(IMCP)to meet this demand.By operating nearly 1000 instruments encompassing all latitudes along with the 120°E–60°W longitudes,IMCP aims,for the first time,to construct comprehensive 3D data representation of the atmosphere and geospace on a global scale and empower interdisciplinary research to tackle key questions related to Earth’s environment and climate change. 展开更多
关键词 International Meridian Circle Program Chinese Meridian Project Ground-based observation Space weather Solar-terrestrial physics
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外源GABA对碱性盐胁迫下猴樟幼苗呼吸代谢相关酶活性的影响 被引量:1
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作者 任莉雯 杨力行 +3 位作者 魏李彤 周德玥 周仪容 韩浩章 《安徽农学通报》 2024年第8期56-60,共5页
碱性盐胁迫影响植物的正常生长发育,γ-氨基丁酸(GABA)能有效缓解盐碱逆境对植物的伤害。本研究以猴樟幼苗为材料,共设5个处理,分别喷施0(对照)、30、50、100和150μmol/L的GABA溶液,选择琥珀酸脱氢酶(SDH)、丙酮酸脱氢酶(PDH)、苹果酸... 碱性盐胁迫影响植物的正常生长发育,γ-氨基丁酸(GABA)能有效缓解盐碱逆境对植物的伤害。本研究以猴樟幼苗为材料,共设5个处理,分别喷施0(对照)、30、50、100和150μmol/L的GABA溶液,选择琥珀酸脱氢酶(SDH)、丙酮酸脱氢酶(PDH)、苹果酸脱氢酶(MDH)、柠檬酸合成酶(CS)和异柠檬酸合成酶(ICDH)指标,研究外源GABA处理对猴樟幼苗呼吸代谢相关酶活性的影响,为植物响应碱性盐胁迫的机理研究提供依据。结果表明,外源喷施30~50μmol/L浓度的GABA处理能明显提高碱性盐胁迫下猴樟幼苗叶片的SDH、PDH、MDH、CS和ICDH活性;100~150μmol/L浓度的GABA处理对呼吸代谢相关酶活性的促进作用不明显;随着外源GABA处理浓度的增加,猴樟幼苗的耐碱性盐胁迫能力综合评价值D呈先增加后降低的趋势,综合评价值D在30~50μmol/L浓度的GABA处理条件下达最大值,而100~150μmol/L浓度的GABA处理条件下D值低于对照。因此,30~50μmol/L浓度的GABA处理能促进碱性盐胁迫下的猴樟幼苗呼吸代谢能力。 展开更多
关键词 GABA 碱性盐胁迫 呼吸代谢 猴樟 PDH活性
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Progress of International Meridian Circle Program 被引量:1
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作者 LIU William MICHEL Blanc +9 位作者 WANG Chi XU Jiyao LI Hui ren liwen LIU Zhengkuan ZHU Yajun LI Guozhu LI Lei ZEren Zhima YANG Fang 《空间科学学报》 CAS CSCD 北大核心 2022年第4期584-587,共4页
Based on the Chinese Meridian Project(CMP),the International Meridian Circle Program(IMCP)aims to coordinate the deployment of a comprehensive ground-based monitoring network along the 120°E-60°W Great Merid... Based on the Chinese Meridian Project(CMP),the International Meridian Circle Program(IMCP)aims to coordinate the deployment of a comprehensive ground-based monitoring network along the 120°E-60°W Great Meridian Circle to track the propagation and evolution of space weather events from the Sun to the Earth,as well as the imprints of other major natural and anthropic hazards on the ionosphere,the middle and upper atmosphere.Currently,we have completed the IMCP headquarters building in Beijing and established the China-Brazil Joint Laboratory for Space Weather in cooperation with Brazil.Meanwhile,the Chinese Meridian Project PhaseⅡand different components of the IMCP observation system are under construction. 展开更多
关键词 Chinese Meridian Project(CMP) Global ground monitoring Space weather International Meridian Circle Program(IMCP)
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Recent Development and Preliminary Results of Chinese Meridian Project 被引量:1
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作者 WANG Chi ren liwen 《空间科学学报》 CAS CSCD 北大核心 2013年第1期1-5,共5页
The Meridian Project is a ground-based network program to monitor solar-terrestrial space environment,which consists of a chain of 15 ground-based observatories located roughly along 120°E longitude and 30°N... The Meridian Project is a ground-based network program to monitor solar-terrestrial space environment,which consists of a chain of 15 ground-based observatories located roughly along 120°E longitude and 30°N latitude.The Meridian project started in 2008,and its construction was completed by 2011.The integration and test phase of the Meridian Project conducted in 2011 demonstrated its observation capabilities as expected.The project will be in full operation in 2012. This report gives an overview of the recent development and preliminary results of the Meridian Project since 2010. 展开更多
关键词 Meridian Project Space weather Ground-based
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Dust Acoustic Wave in Dusty Plasmas With Streaming Ions Under Ultraviolet Irradiation
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作者 ren liwen WANG Chi 《空间科学学报》 CAS CSCD 北大核心 2012年第2期191-196,共6页
The reductive perturbation method is applied to investigate the dust acoustic soliton in dusty plasmas with streaming ions under ultraviolet irradiation theoretically and numerically.The self-consistent dust charge va... The reductive perturbation method is applied to investigate the dust acoustic soliton in dusty plasmas with streaming ions under ultraviolet irradiation theoretically and numerically.The self-consistent dust charge variation is taken into account.It is shown that the ultraviolet irradiation can significantly lower the magnitude of the dust negative charge,and ion streaming velocity firstly raise the magnitude of the dust negative charge and then lower it.With the growth of(Ultraviolet) UV photo flux or ion streaming velocity,the phase velocity and width of the solitary waves decrease, whereas its amplitude increases. 展开更多
关键词 Dusty plasma Solitary wave Ultraviolet irradiation Streaming ion
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Progress of International Meridian Circle Program
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作者 WANG Chi BLANC Michel +13 位作者 ZHANG Shunrong DENARDINI Clezio Marcos LIU William SHEN Xuhui WU Jian XU Jiyao LI Hui ZHANG Qinghe ren liwen ZHU Yajun LI Guozhu DING Zonghua LIU Zhengkuan YANG Fang 《空间科学学报》 CAS CSCD 北大核心 2024年第4期741-745,共5页
In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the I... In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the International Meridian Circle Program(IMCP).The IMCP aims to integrate and establish a comprehensive network of ground-based monitoring stations designed to track the propagation of space weather events from the Sun to Earth.Additionally,it monitors various disturbances generated within the Earth system that impact geospace.Over the past two years,significant progress has been made on the IMCP.In particular,the second phase of construction for the China-Brazil Joint Laboratory for Space Weather has been completed,and the North Pole and Southeast Asia networks are under active construction.The 2024 IMCP joint observation campaign was successfully conducted.To facilitate these developments,the scientific program committee of IMCP was established,following the success of 2023 IMCP workshop and the space weather school,which was co-hosted with the Asia-Pacific Space Cooperation Organization(APSCO)and sponsored by Chinese Academy of Sciences(CAS)and Scientific Committee on Solar-Terrestrial Physics(SCOSTEP).Preparations are now underway for the 2024 workshop in collaboration with the National Institute for Space Research(INPE)in Brazil. 展开更多
关键词 Chinese Meridian Project(CMP) International Meridian Circle Program(IMCP) China-Brazil Joint Laboratory for Space Weather North Pole and Southeast Asia networks
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